Charging handles for this type of firearm system have been described since the very first version of Eugene Stoner's original firearm design universally first known as the AR-15 type rifle, and later adopted by various militaries as the “M16” series.
There were several iterations of the basic charging handle designed, tested, and proposed for military adoption, and later on for commercial sales. The earliest Stoner-inspired design had a semi-triangular shape where the base of the triangle form was the rear face of the handle and the other two sides were alternately formed on the right by an extension of the base, and on the left side by the receiver retaining latch itself. When activated, the operator was required to simultaneously grasp the right side face of the handle while also grasping and restraining the left side latch and retracting the entire charging handle assembly in order to charge the firearm. Rearward pressure was intended to be applied only upon the two “forward” sides of the triangle form. The irregular geometric shape of this early design when grasped to open the latch, combined with the physically small triangular surfaces available made rapid or off-side charging of the firearm extremely difficult, if not entirely impossible under certain operational conditions.
It has been recognized then, since the very earliest stages of development of this firearm system, that rapid, effective, charging of the firearm is largely dependent upon the available dexterous grasping surfaces of the charging handle and the ability of the operator to grasp and manually depress/squeeze the receiver retaining latch prior to withdrawing the handle assembly. The entire series of these charging handles in the art was designed solely around right-handed operators and has never been easy, sure, or efficient for left-handed operators to function, or even right-handed operators using the handle in the off-side, or slung positions.
When it was realized that the original triangular plan form was inefficient and difficult to use the charging handle's external grasping surface shape was redesigned. The resulting finalized compromise shape was described as being approximately in the shape of a capital letter “T” form, with the transverse member of the “T” acting now as the grasping handle. Rather than pulling exclusively on the heavily slanted sides of the triangular form as with the original design, the operator now was trained to grasp both the front and rear surfaces of the left side of the transverse member between the forefinger and thumb. With this grip, this meant that the left side receiver retention latch had to be squeezed before the charging handle could be retracted to cock or charge the firearm. In this basic form the charging handle assembly has been standardized, adopted for service use and commercial sale, and has remained essentially unchanged since the early 1960's. This basic form is still the standard issue form for all service and commercial variations of this family of firearms. Despite the standardization of this later design, little has been done in the ensuing years to improve upon the inherent problems and defects of effective grasping of the less than ideal shape of the handle, combined with the need to manually function the left side receiver retention latch, exclusively. This was already a significant enough difficulty for right-handed operators of the firearm system but when left handed or even off-side charging was contemplated, the tactile problems become nearly insurmountable, thus contributing significantly to the operator's loss of effectiveness or rapidity in charging the firearm, especially under immediate action requirements, such as during military combat or police enforcement operations. As understood in the art, under such critical circumstances it may be vital to keep one's finger on the trigger for self-defensive purposes while recharging the weapon with the opposing hand.
Several attempts have been made to resolve this problem of charging such firearm systems by the provision of ambidextrous charging handles. U.S. Pat. Nos. 3,225,653 (Packard), 7,240,600 (Bordson) and WIPO application WO2007/090611 (Fluhr, et al.) all disclose prior art versions of ambidextrous charging handles. However, in all of these charging handles multiple separate latch grasping surfaces are used. Packard required both latches to be grasped and squeezed simultaneously to allow operation of the charging handle. Bordson and Fluhr, et al. require either one or both of the latches to be grasped and squeezed to allow operation of the charging handle. What is needed instead is a charging handle that allows for truly ambidextrous operation from either side of the charging handle while at the same time allowing for efficient operation from any available angle or contact point so long as a simple straight line retraction can be made, and at the same time eliminating the requirement to depress a separate latch before commencing the firearm charging operation.